An investigation of the structure and function of the myosin light chain kinase (MLCK) gene has been initiated. Using recombinant DNA technology we will construct both cDNA and genomic libraries from turkey gizzard and rat uterus tissue. Upon identification and isolation of the gene for MLCK, we will determine the base characteristics of the gene such as its sequence, copy number and gene family. We plan to study the molecular mechanisms underlying the control of expression of MLCK gene and its role in the processes of malignant transformation and growth control. The technique of low angle platinum shadowing will be used to generate replicas of myosin light chain kinase molecules for direct observation by electron microscopy. Rotary shadowed replicas will provide information on the contour length and width of the molecule. Fixed angle shadowing reveal the topographical distribution of globular and linear domains within the molecule. Such replicas will be made of myosin light chain kinase from platelet, dog trachea and turkey gizzard. The effect of calcium-calmodulin as well as phosphorylation on the morphology of the kinases shall also be investigated.